Low-Molecular-Weight Heparin Administration in Renal Disease
Low-Molecular-Weight Heparin Administration in Renal Disease
The data presented by Brophy and colleagues are a good beginning to our understanding of the pharmacokinetics of enoxaparin in patients requiring dialysis. Still, there are too many unanswered questions based on the small number of patients, administration of a single dose of enoxaparin, and pharmacokinetic simulation used to support their conclusions.
Other researchers discussed the use of low-molecular-weight heparins (LMWHs) in patients with renal insufficiency. Patients with impaired renal function who receive multiple doses of LMWH have higher anti-Xa levels, reduced drug clearances, and prolonged drug half-lives. Clear guidelines on dosage adjustments for LMWHs given to patients with end-stage renal disease (ESRD)have not been published.
Investigators retrospectively evaluated the frequency of bleeding and use of blood products in patients with renal insufficiency compared with those with normal renal function who received multiple doses of LMWH. Patients with renal insufficiency were more likely to have bleeding complications and require transfusions than those with normal renal function. Our own (limited, unpublished) experience using multiple doses of LMWH in patients with renal dysfunction led us to believe that these patients are at higher risk for hemorrhage compared with patients with normal renal function.
As very few patients receive a single therapeutic dose of LMWH, it is premature to state that monitoring and dosing adjustments are unnecessary in patients with ESRD who receive multiple doses of LMWH.
The data presented by Brophy and colleagues are a good beginning to our understanding of the pharmacokinetics of enoxaparin in patients requiring dialysis. Still, there are too many unanswered questions based on the small number of patients, administration of a single dose of enoxaparin, and pharmacokinetic simulation used to support their conclusions.
Other researchers discussed the use of low-molecular-weight heparins (LMWHs) in patients with renal insufficiency. Patients with impaired renal function who receive multiple doses of LMWH have higher anti-Xa levels, reduced drug clearances, and prolonged drug half-lives. Clear guidelines on dosage adjustments for LMWHs given to patients with end-stage renal disease (ESRD)have not been published.
Investigators retrospectively evaluated the frequency of bleeding and use of blood products in patients with renal insufficiency compared with those with normal renal function who received multiple doses of LMWH. Patients with renal insufficiency were more likely to have bleeding complications and require transfusions than those with normal renal function. Our own (limited, unpublished) experience using multiple doses of LMWH in patients with renal dysfunction led us to believe that these patients are at higher risk for hemorrhage compared with patients with normal renal function.
As very few patients receive a single therapeutic dose of LMWH, it is premature to state that monitoring and dosing adjustments are unnecessary in patients with ESRD who receive multiple doses of LMWH.
Brophy DF, Wazny LD, Gehr TWB, Comstock TJ, Ventiz J. The pharmacokinetics of subcutaneous enoxaparin in end-stage renal disease. Pharmacotherapy 2001;21:169-74.
Duplaga BA, Rivers CW, Nutescu E. Dosing and monitoring of low-molecular-weight heparins in special populations. Pharmacotherapy 2001;21:218-34.
Gerlach AP, Pickworth KK, Seth SK, Tanna SB, Barnes JF. Enoxaparin and bleeding complications: a review in patients with and without renal insufficiency. Pharmacotherapy 2000;20:771-5.
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